Entrainer-enhanced Reactive Distillation
نویسندگان
چکیده
The paper presents the use of a Mass Separation Agent (entrainer) in reactive distillation processes. This can help to overcome limitations due to distillation boundaries, and in the same time increase the degrees of freedom in design. The catalytic esterification of fatty acids with light alcohols C2-C4 is studied as application example. Because the alcohol and water distillate in top simultaneously, another separation is needed to recover and recycle the alcohol. The problem can be solved elegantly by means of an entrainer that can form a minimum boiling ternary heterogeneous azeotrope. Water can be removed quantitatively by decanting, or by an additional simple stripping column. The use of entrainer has beneficial effect on the reaction rate, by increasing the amount of alcohol recycled to the reaction space. The paper discusses in more detail the design of a process for the esterification of the lauric acid with 1-propanol. The following aspects are investigated: chemical and phase equilibrium, entrainer selection, kinetic design, and optimisation. Minimum and maximum solvent ratio has been identified. A significant reduction of the amount of catalyst can be obtained compared with the situation without entrainer.
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